Guinea pig with white chest patch

I lost my little guinea pig yesterday around 3pm. He's a small, tawny-brown pig with a distinct white chest patch and a tiny notch in his left ear. Last seen outside the Walmart supercenter on 34th Street in Amarillo, I had him in a blue travel cage when I left the parking lot. This little guy is more than a pet—it's a gift from my sister, and I'm really worried about him. If anyone found him, please let me know; I’d be so grateful to get him back.